#!/usr/bin/env node

const mysql=require('mysql2/promise'),
      log=console.table;

let db={};

db.insert=async(con,areaName)=>{
  const sql=`insert into areas(area_name) values('${areaName}')`;
  const [res]=await con.query(sql);
  log(res);
}

db.update=async(con,id,areaName)=>{
  const sql=`update areas set area_name = '${areaName}' where id = ${id}`;//因为area_name是String需要加''，id是Number不需要
  const [res]=await con.query(sql);
  log(res);
};

db.del=async(con,id)=>{
  const sql=`delete from areas where id=${id}`;
  const [res]=await con.query(sql);
  log(res);
}

db.select = async(con)=>{
  const sql='select * from areas order by id';
  const [rows]=await con.query(sql);
  log(rows);
};

(async()=>{
  const con=await mysql.createConnection({
    host:'127.0.0.1',
    user:'root',
    password:'ddd',
    database:'demo'
  });
  await db[process.argv[2]](con,process.argv[3],process.argv[4]);
  await con.end();
})();







